<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>yuefen</title>
</head>
<body>


<script>



    var x = prompt("请输入月份");


    if (x <=12){
        if(x <= 10 && x >= 5){
            var d = prompt("经济舱还是商务舱");
            if(d == "商务舱"){
                alert("2000元");
            }else if(d == "经济舱"){
                alert("800元");
            }
        }else{
            var m = prompt("经济舱还是商务舱");
            if(m == "商务舱"){
                alert("800元");
            }else if(m == "经济舱"){
                alert("200元");
            }
        }
    }else{
        alert("请输入月份");
    }






</script>
</body>
</html>